A NOSE FOR RUNNING
Mice bred for running have different noses
A whiff of your gym bag might make you wince, but your nose could be the key to getting fit. 0ew research carried out on mice suggests there’s a link between doing exercise and the expression of genes that relate to scent perception.
In a study by Sachiko Haga-Yamanaka and colleagues at the University of California, Riverside, mice were placed on a running wheel. Some of the mice voluntarily spent more time running on the wheel and the scientists dubbed them “high-runner mice”. The high-runner mice were bred together, and their offspring were watched on the wheel. High runners were chosen again from this second generation and selectively bred, and so on, until the team had established a line of mice that were bred to be high runners.
“Voluntary wheel running (VWR) is an intrinsically motivated and naturally rewarding behaviour [for mice], and even wild mice run on a wheel placed in nature,” wrote the researchers in their paper.
They then compared the high-runner mice to a control group, who hadn’t been selectively bred.
.ooking specifically at a part of the olfactory system
called the vomeronasal organ – located in the noses of mice and humans – and its corresponding neurons in the brain, the researchers noticed that there were 132 genes changed in the high runners.
“The olfactory system became genetically differentiated between the high-runner and control lines during the selective breeding process,” said Haga-Yamanaka. “Our results suggest these chemosensory receptors [which were expressed by the altered genes] are important trait locations for the control of voluntary exercise in mice.”
The vomeronasal organ detects pheromones, chemicals produced by animals that end up in the air. This new knowledge could one day form the
basis of a scent that motivates you to get fitter.
It’s not yet clear if these odours work by increasing the mouse’s motivation for exercise, or if it boosts the neurological ‘reward’ it gets when it’s running.
“It’s not inconceivable that someday we might be able to isolate the chemicals and use them like air fresheners in gyms to make people even more motivated to exercise,” said co-author Theodore Garland Jr. “In other words: spray, sniff, and squat.”